Overview
Online design
Sample & Buy
Solutions
Documentation
CAD Resources
Tools & Software
Quality & Reliability
Get Started
Partner products
Sales Briefcase

Product overview

Description

The UC284xB family of control ICs provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include a trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lockout featuring start-up current less than 0.5mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off-state. Differences between members of this family are the under-voltage lockout thresholds and maximum duty cycle ranges. The UC2842B and UC2844B have UVLO thresholds of 16V (on) and 10V (off), ideally suited off-line applications The corresponding thresholds for the UC2843B and UC2845B are 8.5V and 7.9V. The UC2842B and UC2843B can operate to duty cycles approaching 100%. A range of the zero to < 50 % is obtained by the UC2844B and UC2845B by the addition of an internal toggle flip flop which blanks the output off every other clock cycle.
  • All features

    • LOW START-UP AND OPERATING CURRENT
    • UNDERVOLTAGE LOCKOUT WITH HYSTERESIS
    • INTERNALLY TRIMMED REFERENCE WITH UNDERVOLTAGE LOCKOUT
    • CURRENT LIMITING
    • TRIMMED OSCILLATOR FOR PRECISE FREQUENCY CONTROL
    • CURRENT MODE OPERATION TO 500kHz
    • OSCILLATOR FREQUENCY GUARANTEED AT 250kHz
    • LATCHING PWM FOR CYCLE-BY-CYCLE
    • HIGH CURRENT TOTEM POLE OUTPUT
    • AUTOMATIC FEED FORWARD COMPENSATION

Circuit Diagram

Recommended for you

EDA Symbols, Footprints and 3D Models

STMicroelectronics - UC2844B

Speed up your design by downloading all the EDA symbols, footprints and 3D models for your application. You have access to a large number of CAD formats to fit with your design toolchain.

Symbols

Symbols

Footprints

Footprints

3D model

3D models

Quality and Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
UC2844BD1
Active
SO-8 Industrial Ecopack2
UC2844BD1013TR
Active
SO-8 Industrial Ecopack2
UC2844BN
Active
DIP-8 Industrial Ecopack2

UC2844BD1

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

UC2844BD1013TR

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

UC2844BN

Package:

DIP-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

DIP-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.

Sample & Buy

Part Number
Order from Distributors
Order from ST
Marketing Status
ECCN (US)
ECCN (EU)
Packing Type
Package
Temperature (°C) Country of Origin
Budgetary Price (US$)*/Qty
min
max
UC2844BD1 Available at 3 distributors

Distributor availability ofUC2844BD1

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 883 1 Order Now
MOUSER WORLDWIDE 2748 1 Order Now
Farnell Element14 EUROPE 3314 1 Order Now

Distributor reported inventory date: 2021-05-17

Distributor Name

DIGIKEY

Stock

883

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

2748

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

3314

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-05-17

Buy Direct
Active
EAR99 NEC Tube SO-8 - - MOROCCO 0.3643 / 1k
UC2844BD1013TR Available at 4 distributors

Distributor availability ofUC2844BD1013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1138 1 Order Now
Newark Element14 AMERICA 83 0 Order Now
MOUSER WORLDWIDE 2407 1 Order Now
Farnell Element14 EUROPE 1414 1 Order Now

Distributor reported inventory date: 2021-05-17

Distributor Name

DIGIKEY

Stock

1138

Min.Order

1

Region

WORLDWIDE Order Now

Newark Element14

Stock

83

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

2407

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1414

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-05-17

Buy Direct
Active
EAR99 NEC Tape And Reel SO-8 - - MOROCCO 0.3643 / 1k
UC2844BN Available at 5 distributors

Distributor availability ofUC2844BN

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1748 1 Order Now
AVNET AMERICA 750 0 Order Now
Newark Element14 AMERICA 51 0 Order Now
MOUSER WORLDWIDE 468 1 Order Now
Farnell Element14 EUROPE 1790 1 Order Now

Distributor reported inventory date: 2021-05-17

Distributor Name

DIGIKEY

Stock

1748

Min.Order

1

Region

WORLDWIDE Order Now

AVNET

Stock

750

Min.Order

0

Region

AMERICA Order Now

Newark Element14

Stock

51

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

468

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1790

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-05-17

Buy Direct
Active
EAR99 NEC Tube DIP-8 - - CHINA 0.3643 / 1k

UC2844BD1

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

0.3643 / 1k

Distributor availability ofUC2844BD1

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 883 1 Order Now
MOUSER WORLDWIDE 2748 1 Order Now
Farnell Element14 EUROPE 3314 1 Order Now

Distributor reported inventory date: 2021-05-17

Distributor Name

DIGIKEY

Stock

883

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

2748

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

3314

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-05-17

ECCN (EU)

NEC

Packing Type

Tube

Package

SO-8

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

0.3643 / 1k

Country of Origin

MOROCCO

UC2844BD1013TR

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

0.3643 / 1k

Distributor availability ofUC2844BD1013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1138 1 Order Now
Newark Element14 AMERICA 83 0 Order Now
MOUSER WORLDWIDE 2407 1 Order Now
Farnell Element14 EUROPE 1414 1 Order Now

Distributor reported inventory date: 2021-05-17

Distributor Name

DIGIKEY

Stock

1138

Min.Order

1

Region

WORLDWIDE Order Now

Newark Element14

Stock

83

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

2407

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1414

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-05-17

ECCN (EU)

NEC

Packing Type

Tape And Reel

Package

SO-8

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

0.3643 / 1k

Country of Origin

MOROCCO

UC2844BN

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

0.3643 / 1k

Distributor availability ofUC2844BN

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1748 1 Order Now
AVNET AMERICA 750 0 Order Now
Newark Element14 AMERICA 51 0 Order Now
MOUSER WORLDWIDE 468 1 Order Now
Farnell Element14 EUROPE 1790 1 Order Now

Distributor reported inventory date: 2021-05-17

Distributor Name

DIGIKEY

Stock

1748

Min.Order

1

Region

WORLDWIDE Order Now

AVNET

Stock

750

Min.Order

0

Region

AMERICA Order Now

Newark Element14

Stock

51

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

468

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1790

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-05-17

ECCN (EU)

NEC

Packing Type

Tube

Package

DIP-8

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

0.3643 / 1k

Country of Origin

CHINA

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors